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Free English Tool
Unit Converter
Type one value and it is converted into every other unit of the same kind at once. Korean units such as pyeong, geun and don are included too.
Nothing you type ever leaves your browser.
Enter a value and the results will appear here.
Conversion results
Numbers are shown to roughly 10 significant digits (slightly fewer or more depending on the size of the value). Units with no fixed definition — Mach, month, year — are marked approx. next to the result.
How to use
- 1
Pick what you are converting
Choose length, weight, volume, temperature, area, speed, time, data, energy, power or pressure. The units inside the category you picked are listed right underneath.
- 2
Enter the value and the source unit
For a Korean apartment floor area, for example, type 84 and choose Square meter. Commas and fractions such as 1 1/2 are read correctly.
- 3
See every unit at once
There is no button to press — the moment you type, the value is converted into every unit of the same kind. You never have to pick a target unit and recalculate one by one.
- 4
Copy only what you need
The Copy button on each row copies the number alone, so it pastes straight into a calculator or a spreadsheet. Copy all results at the bottom takes every row at once.
Conversion factors worth knowing
The values below are defined — fixed by international agreement or by the Korean traditional system of measures. They are used exactly as written, not rounded.
- 1 inch = 2.54 cm — set by the 1959 international yard and pound agreement. A foot is 12 inches, a yard is 3 feet, a mile is 1,760 yards.
- 1 pyeong = 400/121 m² ≈ 3.305785 m² — pyeong is the Korean area unit still used for homes and land. One pyeong is a square of 6 ja (1 ja = 10/33 m). An 84 m² apartment is 25.41 pyeong; 59 m² is 17.85 pyeong.
- 1 pound = 0.45359237 kg — an ounce is 1/16 of a pound, or 28.349523125 g.
- 1 geun = 600 g (meat), 375 g (vegetables and fruit) — geun is a Korean market unit whose value depends on what you are buying. 1 don is 3.75 g, 1 nyang is 10 don, 1 gwan is 1,000 don.
- °C = (°F − 32) × 5/9 — temperature is not a plain multiplication. 0 °C is 32 °F, 100 °C is 212 °F, and −40 is the same on both scales.
- 1 US gallon = 3.785411784 L — the imperial gallon is different, at 4.54609 L. A US fluid ounce is 29.5735 mL; a US cup is 236.588 mL.
- 1 metric horsepower (PS) = 735.49875 W — Korean and European car specs quote PS. The mechanical horsepower (hp) used in the US and UK is slightly larger, at 745.6999 W.
- 1 kcal = 4,184 J = 4.184 kJ — the "calorie" on food packaging is a kilocalorie. 1 kWh is 3,600 kJ.
- 1 GB = 1,000,000,000 bytes, 1 GiB = 1,073,741,824 bytes — this is why a 500 GB drive shows up as 465.66 on your computer.
Frequently asked questions
How many square meters is one pyeong?
One pyeong is 400/121 m², about 3.305785 m². The other way round, 1 m² is about 0.3025 pyeong. An 84 m² apartment is 25.41 pyeong and 59 m² is 17.85 pyeong. This tool uses the exact defined value, not a rounded one.
Is a geun of meat different from a geun of vegetables?
Yes. At a butcher's, one geun is 600 g, but in vegetable and fruit markets 375 g is commonly called a geun. Both are listed separately, so pick the one that matches your situation. The don used by jewellers is 3.75 g.
How do I convert Celsius and Fahrenheit?
°C = (°F − 32) × 5/9 and °F = °C × 9/5 + 32. The two scales start from different zero points, so multiplying alone will not give the right answer. 0 °C is 32 °F, and at −40 the two scales meet.
Is a US gallon different from an imperial gallon?
Yes. The US gallon is 3.785411784 L and the imperial gallon is 4.54609 L — about 20% apart. Fluid ounces differ too: 29.5735 mL in the US, 28.4131 mL in the UK. For a US product label, pick the US units.
Why are there two kinds of horsepower?
Korean and European car specifications use metric horsepower (PS) at 735.49875 W, while the US and UK use mechanical horsepower (hp) at 745.6999 W. The gap is about 1.4%, so it widens as the number grows. Both are included here.
Why do GB and GiB give different numbers?
GB counts in powers of 1,000 and GiB counts in powers of 1,024. Drive manufacturers label in GB while Windows shows the 1,024-based figure and still calls it "GB". That is why a 500 GB drive appears as 465.66.
Can I trust the numbers exactly?
The conversion factors are the defined values from international agreements and the Korean traditional system. The screen shows about 10 significant digits, so the last digit may differ. Units with no fixed definition — Mach, month, year — are marked approx., so please check the basis before quoting them in an official document.
Can I enter fractions or values with commas?
Yes. Values with commas such as 1,234.5, fractions such as 3/4 or 1 1/2, negative values such as −40 and exponent notation such as 1.2e3 are all recognised. If the text cannot be read as a number, a short message explains what to fix.